Beam compass



July 10, 1928'.

F. SCHWARTZ BEAM COMPASS.

Filed May 17, 1926 um/" 6oz,

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Patented July 10, 1928.

' FRANK soiiwanr'z onnnw 612K, N. y.

BEAM amiss; I a

ing instruments and more particularly to of the class described, meanswhereby bows o 'in a novel constructionof'means'for carry member for retaining aselected bow-pen in pens, or bow-pencils having spring arms of varying widths may be selectively accommodated and rigidly lield'in position, said means engaging only the:pivot pin arm of the selected instrument,v the pencil orpen arm 7 being free to be adjusted: by the usual thumb nutorpthe like. 3 ,An'other' feat-ureof he'invention i esides ing and locking the pivot point at a desired pointalong the'be'aml I A further feature resides in the provision of a. clamping plate or engagement tilted operative position wherein the pen rests on the paper while the opposite pivotpin is held elevated therefrom.

In the drawings: 1 Fig. lis a side elevation of an improved beam-compass with the clamping devices in position.

Fig. 2 is an enlarged section on the line ment in the thickness ofthe pens received 22 of Fig. 1. I

Fig. 3 is a detail perspective of an 1111- proved clip plate or engagement member.

Figs. 4 and 5.are elevational and end sectional views respectively of a modifiedform of clamping device. I a

Referring to the drawings, on the beam 10 is carried a pivot pin 11, and'a bow pen 12, of the usual form." In carrying out. my

; invention, I provide means for holding the pivot pin arm 13 of the bow pen in rigid relation with the beam while the pen arm 1a of said bow pen is free to be adjusted by the thumb nut 15. The diiferent makes of bow pens available on the market have arms 7 of different. widths and to accommodate these various sizes, I provide a clip plate or engagement member, compr sing an mtegral blank having a medial body portion 17 and crimped instrument-accommodating' ends. The latter are constituted of angu- Application filed may 17',

1926: Serial at; 109,616."

larly bent ends18 andl9, portions 22 and 23, and terminal flanges Q-lgand 25, which" construction form's grooves 26 and27' to receive the arm 1310f the bow pen. i f

The instrument-engaging member is accomn'iodated in'a sleeve element 28 loosely and slida'bly encircling the beam10. The instrument engaging member is clamped in position against the beam with'jone crimped' end clamping the arm 13 of the bow ,pen

againstthe-beam, by means of a thumb screw 29 engaging in athreaded bore in the element.- 28,- as shown, and permitting a certain play between the mstrument'sengaging mem-' her and the sleeve: 28 to-accommodate various sized;instruments of a drawing'set suchlas the bow pen 12.x;

' As shown inyltigs. 1 and 3 offthe'dra-wings, the channeled crimped ends? are arranged with the channels at an angle to the longitudinal center of the engagementinember so that the arm 13 of the'bow pen isheld at an angle to f the perpendicular. while the pen arm lti Of said bow :pen may operate'at the perpendicular or ,substantially'so, as'the thumb nut is adjusted in the operation of the instrument. 1

As clearly shown in Fig. 2, the channel 27 is deeper than the channel 26 to accommo-' 7 date bow pens with wider arms, as1 will be readily understood. I will also call atten tion to the fact that'as shown in Fig. 2

the channels 26 and 27 are much wider than the thickness of the clamped pen arm. This also is to permit of a wide range of adjustby my device andintheir angles to the ver- 31 to confine it in a sleeve element 32 which encircles the beam 10,and is clampable to the beam by a thumb-screw 33. Pin 11 may also have an upward extension handle 11- to facilitate the manipulation of the'beam compass.

In the construction shown in Figs. 4: and i 5 of the drawings, there is shown a strap 34:,

which is bent around the beam 10 and over the medial body portion 17 of the instrupm 11 is preferably soldered,.

ment engaging member, the strap terminals forming spaced ears 35,] through which a thumb screw 36 passes into engagement with a nut 37, to clamp the engagement member in position on the beam.

The operation and utility of the beam compass constructed as above set forth will be apparent withoutfurther description and while there are illustrated preferred embodiments of the invention, it will be ob vious that the structural elements thereof are susceptible to such further variations and modifications as fall within the scope of the appended claims.

What I claim asnew, is

1. In a beam compass, a beam, an engagement member comprising an integral blank having a medial body portion and crimpcd ends for selective accommodation thereunder and against the beam of instruments of a drawing set, and a clamping device for said member, said device comprising a sleeve element slidably engaging about the beam and adapted to accommodate said body portion between one side thereof and one side of the beam so as to hold and engage the instrumentagainst the beam, and means for simultaneously securing said body portion to the clamping device and to the beam.

2. In a beam compass, a beam, in engagement member comprising an integral blank having a medial body portion and crimped ends for selective accommodation thereunderand against the beam of instruments of a drawing set, and a clamping device for said member, said device comprising a sleeve element slidably engaging about the beam and adapted to accommodate said body portion between one side thereof and one side of the beam so as to hold and engage the instrument against the beam, and means for simultaneously securing said body portion to theclampingdevice and to the beam, said last named means comprising an adjustable threaded element associated with the clamping device and adapted to bear against said body portion and through the latter against the beam to force one side of the sleeve element against one side of the beam.

3. In a beam compass, a beam, an'instrument-engaging member comprising an integral blank having a medial body portion and crimped instrumentaccommodating ends, and. a clamping device for securing said member in desired position along the beam, said clamping device comprising a sleeve element having a threaded bore and slidably engaging about the beam, said sleeve element being adapted to accommodate said body portion beneath said bored side, and a threaded element mounted in said bore and engaging said body portion, whereby adjustment of the threaded element will frictionally grasp the beam between said body portion and the opposite side of the sleeve element.

Signed at New York, in the county of New York, and State of New York, this 8th .dayof May, A. D. 1926.

RANK SCHWARTZ. 

